Multi-component apparatuses are common. Examples include electrophotographic printing presses, laser recorders, scanners, copiers, medical diagnostic equipment, coating apparatus, chemical processing apparatus, packaging apparatus, waste disposal apparatus and the like. One example of a multi-component apparatus to which the present invention is particularly relevant is an apparatus for the processing of photographic sheet material, such as X-ray film, pre-sensitised plates, graphic art film and paper, and offset plates. As a rule, a processing apparatus for photographic sheet material comprises several vessels each of which contains a treatment liquid, such as a developer, a fixer and a rinse liquid. The sheet material to be processed is transported through these vessels in turn, by transport means such as one or more pairs of drive rollers, and thereafter optionally to a drying unit. Treatment liquid is pumped into and out of the vessels. The temperature of the treatment liquid in the vessels is usually controlled. One or more vessels may be adapted to expose the sheet material to radiation, in particular to visible light. Visible and/or audible warning signals may be provided to alert the operator to the progress of the processing sequence.
In general terms therefore a typical sheet material processing apparatus, and other multi-component apparatuses, comprises a plurality of operating components and a central processing unit (CPU) operatively linked to these operating components. The CPU contains information concerning at least one desired operating sequence for the apparatus, this information usually being in the form of a programme. The operating components may be "output" operating components such as drive motors and pump motors, or "input" operating components such as temperature sensors and position sensors, but usually the apparatus will include combinations of output and input operating components.
Usually the operating components are connected via an interface board to the host CPU. Several operating components may be connected to the same interface board. If an operating component, such as a pump motor, is connected in this way, the programme running on the host CPU must include information as to the identity of that interface board, and the identity of the connector on that board to which the pump motor is connected, i.e. the "board address" of the pump. If the pump connection is then changed to another connector on the same interface board, or to another interface board, for example because a fault is discovered, the CPU has to be re-programmed with the new board address. Furthermore, the interface board itself has a functionality, new boards requiring new software.
Furthermore, the CPU must be programmed with information concerning the characteristics of the operating component, for example that the pump is of such a nature that the supply of power thereto per unit time will result in a certain volume of liquid being pumped. If the characteristics of the pump are changed, for example because a faulty pump is replaced by one of different characteristics, or it is desired to upgrade the operating components of the apparatus, the CPU has again to be re-programmed with the new pump characteristics in order to ensure predictable operation.
Re-programming of the CPU is disadvantageous, especially since the personnel involved in changing the operating component, i.e. the service engineers, are not necessarily skilled in re-programming and different personnel therefore have to be employed.
U.S. Pat. No. 5491540 (B Mark Hirst/Hewlett-Packard Company) describes a printer or copier apparatus adapted to receive replacement parts that are subject to wear. A control computer is operatively linked to the parts and is pre-loaded with appropriate data that enable identification of a particular replacement part, by reading a serial number stored in a memory chip carried by the replacement part.